First-principles study on the material properties of the inorganic perovskite Rb1-xCsxPbI3 for solar cell applications

Article

关键词: CESIUM LEAD HALIDE;    ELECTRONIC-STRUCTURE;    ANION-EXCHANGE;    NANOCRYSTALS;    CSPBI3;    EFFICIENCY;    BR;    FORMAMIDINIUM;    DEGRADATION;    STABILITY;   

DOI  :  10.1103/PhysRevB.98.125116

来源: SCIE

【 摘 要 】

Recently, replacing or mixing organic molecules in hybrid halide perovskites with inorganic Cs or Rb cations was reported to increase the material stability with comparable solar cell performance. In this work, we systematically investigate the electronic and optical properties of all-inorganic alkali iodide perovskites Rb1-xCsxPbI3 using first-principles virtual-crystal approximation calculations. Our calculations show that with increasing the Cs content x, band gaps, exciton binding energies, and effective masses of charge carriers decrease following the quadratic (linear for effective masses) functions, while lattice constants and static dielectric constants increase following the quadratic function, indicating an enhancement of solar cell performance upon the Rb addition to CsPbI3. By including the many-body interaction within the GW approximation and incorporating the spin-orbit coupling (SOC), we obtain a more reliable band gap compared with experiment for CsPbI3, highlighting the importance of using the GW+SOC approach for the all-inorganic and organic-inorganic hybrid halide perovskite materials.

【 授权许可】

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